fundamentals of database systems 6th edition ppt

... Practical Database Design and Tuning 16.1 The Role of Information Systems in Organizations 16.2 The Database Design Process 16.3 Physical Database Design in Relational Databases 16.4 An Overview of Database ... Using Database Systems 16.1.2 The Information System Life Cycle 16.1.3 The Database Application System Life Cycle 16.1.1 The Organizational Context for Using Database Systems Database systems ... part of the information systems of many organizations In the 1960s information systems were dominated by file systems, but since the early 1970s organizations have gradually moved to database systems...

Ngày tải lên: 08/08/2014, 18:22

... large files and databases To date, it is not well-integrated with database management systems Page 732 of 893 We will briefly review the state of the art of this rather extensive field of data mining, ... coffee} may be such a sequence of itemsets based on three visits of the same customer to the store The support for a sequence S of itemsets is the percentage of the given set U of sequences of ... context of a specific fact 25.8 Applications of Commercial Deductive Database Systems 25.8.1 LDL Applications 25.8.2 VALIDITY Applications We discussed two commercial deductive database systems: ...

Ngày tải lên: 08/08/2014, 18:22

... and Shamkant B Navathe Page 804 of 893 Appendix D: An Overview of the Hierarchical Data Model (Fundamentals of Database Systems, Third Edition) D.1 Hierarchical Database Structures D.2 Integrity ... without defining a view of the database © Copyright 2000 by Ramez Elmasri and Shamkant B Navathe Page 817 of 893 Selected Bibliography (Fundamentals of Database Systems, Third Edition) Format for ... type of the PCR type An occurrence (or instance) of the PCR type consists of one record of the parent record type and a number of records (zero or more) of the child record type A hierarchical database...

Ngày tải lên: 08/08/2014, 18:22

... relation of Figure 5.6 a set of tuples of the form {, ,

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Ngày tải lên: 08/08/2014, 18:22

... 868 Page 11 of 893 We would like to repeat our thanks to those who have reviewed and contributed to both previous editions of Fundamentals of Database Systems For the first edition these individuals ... another C++ program The persistent storage of program objects and data structures is an important function of database systems Traditional database systems often suffered from the so-called impedance ... distinguish between the description of the database and the database itself The description of a database is called the database schema, which is specified during database design and is not expected...

Ngày tải lên: 08/08/2014, 18:22

... soon be reserved for databases containing tens of terabytes 5.1.2 Storage of Databases Databases typically store large amounts of data that must persist over long periods of time The data is accessed ... series of events (e.g., the track stadium may hold many different races) For each event there is a planned date, duration, number of participants, number of officials, and so on A roster of all officials ... whereas main memory is often called volatile storage The cost of storage per unit of data is an order of magnitude less for disk than for primary storage Page 102 of 893 Some of the newer technologies—such...

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... relational databases, users were less concerned about migrating their database applications from other types of database systems for example, network or hierarchical systems to relational systems ... track of dependents database of Figure 07.06, we can get rid of the relation by of employees in the issuing the command: DROP TABLE DEPENDENT CASCADE; If the RESTRICT option is chosen instead of ... aggregate functions on collections of values from the database Examples of such functions include retrieving the average or total salary of all employees or the number of employee tuples Common functions...

Ngày tải lên: 08/08/2014, 18:22

... 10: Examples of Relational Database Management Systems: Oracle and Microsoft Access 10.1 Relational Database Management Systems: A Historical Perspective 10.2 The Basic Structure of the Oracle ... SQL Server (of Sybase, Inc.), SQL Server (of Microsoft), and most recently Access (also of Microsoft, Inc.) They were initially single-user systems, but more recently they have started offering ... offer a whole variety of features needed to accomplish the design and implementation of large databases and their applications An Oracle server consists of an Oracle database the collection of...

Ngày tải lên: 08/08/2014, 18:22

... Trends of Database Technology 13.1.1 The Evolution of Database Systems Technology 13.1.2 The Current Drivers of Database Systems Technology Section 13.1.1 gives a historical overview of the evolution ... historical overview of the evolution of database systems technology, while Section 13.1.2 gives an overview of current trends 13.1.1 The Evolution of Database Systems Technology In the commercial ... interoperability—the interoperation of a number of databases belonging to all of the disparate families of DBMSs—as well as to legacy file management systems A whole series of new systems and tools to deal with...

Ngày tải lên: 08/08/2014, 18:22

... Footnotes The concept of transaction provides a mechanism for describing logical units of database processing Transaction processing systems are systems with large databases and hundreds of concurrent ... the size (number of tuples) of the file that results after the JOIN operation This is usually kept as a ratio of the size (number of tuples) of the resulting join file to the size of the Cartesian ... only on the value of X read by (X) This assumes that computation of the new value of X is a function f(X) based on the old value of X read from the database However, the definition of view serializability...

Ngày tải lên: 08/08/2014, 18:22

... different types of distributed database systems, including federated and multidatabase systems and highlights the problems of heterogeneity and the needs of autonomy in federated database systems, which ... Ramez Elmasri and Shamkant B Navathe Page 629 of 893 Part 6: Advanced Database Concepts & Emerging Applications (Fundamentals of Database Systems, Third Edition) Chapter 23: Enhanced Data Models ... of security in computer systems and databases is outside the scope of this textbook We give only a brief overview of database security techniques here The interested reader can refer to one of...

Ngày tải lên: 08/08/2014, 18:22

... FUNDAMENTALS OF Fourth Edition DATABASE SYSTEMS Ramez Elmasri Department of Computer Science Engineering University of Texas at Arlington Shamkant B N avathe College of Computing ... CONCEPTUAL MODELl NG Databases and Database Users Databases and database systems have become an essential component of everyday life in modern society In the course of a day, most of us encounter ... our thanks to those who have reviewed and contributed to ptevious editions of Fundamentals of Database Systems For the first edition these individuals include Alan Apt (editor), Don Batory, Scott...

Ngày tải lên: 08/08/2014, 18:22

... Local_phone_numbers plays the role of HomePhone, referring to the "home phone of a student," and the role of OfficePhone, referring to the "office phone of the student." 5.1.2 Characteristics of Relations The ... well as of the university's course offerings The database also keeps track of the sponsored research projects of faculty and graduate students This schema is shown in Figure 4.9 A discussion of the ... series of events (e.g., the track stadium may hold many different races) For each event there is a planned date, duration, number of participants, number of officials, and so on A roster of all officials...

Ngày tải lên: 08/08/2014, 18:22

Ngày tải lên: 08/08/2014, 18:22

Ngày tải lên: 08/08/2014, 18:22

Ngày tải lên: 08/08/2014, 18:22

Ngày tải lên: 08/08/2014, 18:22

Ngày tải lên: 08/08/2014, 18:22

Ngày tải lên: 08/08/2014, 18:22